Grinding machine



Feb. 27, 1 934. w. J. GUILD Y GRINDING MACHINE Filed July 20, 1931 6Sheets-Sheet l W \\\\W\ \Q w wo 3. (mad Feb. 27, 1934. w. J. GUILDGRINDING MACHINE Filed July 20, 1931 6 Sheets-Sheet 2 BBO Feb. 2 7,1934.

w. J. GUILD 1,948,914

GRINDING MACHINE Filed July 20, 1931 6 Sheets-Sheet 4 e32 aaz V I I 7 lI kx fi Waldo 3. Guild Feb. 27, 1934. w GUILD 1,948,914

GRINDING MACHINE Filed July 20, 1931 6 Sheets-Sheet 5 Waldo 3: E nil/d;

Feb. 27, 1934. w J GU|LD 1948 9114 GRINDING MACHINE Filed July 20, 19316 Sheets-Sheet 6 Mulder 3: Guild Patented Feb. 27, 1934 UNITED STATESPATENT QFFECE The Heald Machine Company, Worcester,

Mass, a corporation of Massachusetts Application July 20, 1931. SerialNo. 551,922

33 Claims.

The present invention relates to grinding machines and particularly tointernal grinding machines arranged for the automatic finishing of theinternal bore of successive workpieces to a predetermined diameter andfor mechanically inserting successive unground workpieces into andremoving finished workpieces from the workholder.

In the copending application of Highberg, Serial No. 99,287, filed April2, 1926, now Patent No. 1,840,841 the grinding wheel is withdrawn fromthe workpiece and run out a substantial distance from the workholderupon the completion of the grinding operation. At the end of the runout,the movement of the carriage carrying the grinding wheel isautomatically reversed in response to the carriage movement, whereby thewheel is returned into operative relation to the workpiece. During therunout and return of the wheel, a workloading device is operated inresponse to the carriage movements in order to effect the removal of thecompleted workpiece from the workholder and the insertion of an ungroundworkpiece therein. In a machine of this type, if any of the parts failto function properly, the unloading and loading of the workholder is notcompleted before the wheel returns to operative position and themechanism jams or the subsequent entire grinding operation is carriedthrough without a workpiece having been inserted in the holder. One ofthe objects of the present invention is to provide an automatic grindingmachine which incorporates the advantages of a machine of the typedisclosed in the above cited application with none of its disadvantages.

According to the present invention, the can riage carrying the grindingwheel is run out to rest position and initiates during the runout, theoperation of the workloading instrumentalities; the latter proceed toremove the completed workpiece from the workholder and insert anunground workpiece therein, the carriage being returned toward theworkholder to bring the grinding wheel into operative position only whenthe loading mechanism has completed its operation. The workloadingmechanism is arranged to go through the entire operation of removing thecompleted workpiece from the workholder and inserting an ungroundworkpiece therein entirely inde pendently of the operation of thegrinding instrumentalities, that is, after the workloadinginstrumentalities are put in operation, the operation is continued andcarried to completion by instrumentalities forming an integral part ofthe workloading mechanism, the grinding instrumentalities being set inoperation automatically at the completion of the loading operation.

The invention incorporates automatic grinding machine instrumentalitieswhich are arranged to procure the grinding of successive workpieces eachto a predetermined finished size as shown by way of example in thepatent to Taylor 1,682,- 573 issued August 28, 1928, the patent toKempton and Gallimore No. 1,731,719 issued October 15, 1929, or thecopending application of Guild and Burns Serial No. 367,401 filed May31, 1929, now Patent No. 1,830,358, issued November 3, 1931, each ofwhich is arranged to grind successive workpieces to a predetermined sizewhen said workpieces are inserted in the workholder, the machine beingbrought to rest at the completion of each grinding operation. Thepresent invention involves automatic mechanism by which to return thegrinding wheel carriage to the work when an unground workpiece has beenloaded into a workholder by the workloading mechanism. Another object isto provide a grinding machine in which the various instrumentalities areactuated by fluid pressure mechanism. Other objects and advantages ofthe invention will appear as from the following description taken inconnection with the accompanying drawings.

Fig. 1 is a front elevation of an internal grinding machine embodyingthe invention.

Fig. 2 is a fragmentary elevational view showing the reversing members.

Fig. 3 is an isometric view of the workloading mechanism, and theactuating mechanism therefor.

Fig. 4 is a plan view of the actuating mechanism for the workloadingmechanism.

Fig. 5 is a development of the cam shown in Fig. 4, which actuates theworkloading mechanism.

Fig. 6 is an elevational view partly in section of a portion of the camwhich actuates the workloading mechanism.

Fig. 7 is an isometric view of the workloading mechanism.

Fig. 8 is a side elevation of the cylinder and piston which operates theworkloading instrumentalities.

Fig. 9 is a longitudinal sectional view of a certain valve mechanism.

Fig. 10 is an elevational view of the workpositioning means on the lowerend of the workfeeding hopper.

Fig. 11 is a sectional view along the line 11-l1 of Fig. 10 looking inthe direction of the arrows.

Fig. 12 is a side elevation of the lower end of the hopper.

Fig. 13 is a side elevation of the mechanism by which the Work isretained in the hopper and delivered to the workloading mechanism.

Fig. 14 is a wiring diagram.

Fig. 15 is a diagrammatic view of the hydraulic or fluid pressuresystem.

Like reference characters refer to like parts throughout the drawings.

Referring to the drawings, particularly to Fig. 1, the machine providesthe usual reciprocatory table or carriage 1, ordinarily provided in in-.

ternal grinding machines. In such a machine either the grinding wheel orthe work to be ground may be carried on the table 1, the reciprocationof the latter being utilized in either case to produce a relativetraversing movement between the grinding wheel and the work. As hereshown, the table 1 supports and carries a wheelhead 2 of the usualconstruction while the work which is to be operated upon is held in achuck or other suitable work-supporting and rotating mechanism in aworkhead 3, the latter being carried by a bridge 4 which spansslideways, not shown, provided by the machine frame for the back andforth movement of the table 1.

The machine of the present invention utilizes certain mechanisms fromprior patents which are briefly referred to in order more completely tounderstand the invention. A rotating gauge of the type disclosed inReissue Patent No. 16,141 granted to McDonough August 11, 1925, is usedto bring the grinding operation on each successive 35 workpiece to aclose when the workpiece reaches a predetermined finished size. Theautomatic dressing and truing of the grinding wheel by which a truegrinding surface is maintained, is procured by mechanism of the typedisclosed in Patent No. 1,731,719, granted to Kempton and GallimoreOctober 15, 1929, the automatic dressing operation being inaugurated byinstrumentalities similar to the type disclosed in Patent No. 1,682,672granted to Guild, the present applicant, August 28, 1928. Thearrangement of the mechanism which controls the grinding operation oneach workpiece is disclosed in the above identified copendingapplication of Guild, the present applicant, and Burns, Serial No.367,401, filed May 31,

1929, and the application of Guild, the present applicant, Serial No.445,989, filed April 21, 1930, now Patent No. 1,914,995, dated June 20,1933. A brief description of the general operation of the machine inaccordance with these prior patents and applications will be given inorder to disclose a completely automatic grinding machine.

The grinding wheel carriage is arranged for reciprocatory movementlongitudinally of the table 1 in order to procure a traversing movementof the grinding wheel carried by the wheelhead across the surface of theworkpiece being ground, and to this end the machine provides a cylinder5, Fig. 15, which is preferably attached to the base of the machine, thecylinder containing a piston, not shown, whose piston rod 6 is connectedto the carriage 1. I Fluid under pressure is directed alternately toopposite ends of the cylinder 5 by mechanism hereinafter disclosed toprocure the reciprocatory traverse of the carriage.

The normal reciprocatory traverse to procure the working reciprocationof the grinding wheel in operative relation to the workpiece is procuredin the manner disclosed in the above cited Guild Patent No. 1,914,995,by dogs or stops 7 and 3, Fig. 2, carried on the front of the carriage1,

said dogs being arranged alternately to engage with the upwardlyextending arms 10 and 11 of a reversing member 12, Fig. 15, therebyactuating said member to direct fluid under pressure alternately toopposite ends of the cylinder 5 in order to actuate the carriagealternately in opposite directions. The reversing member 12 is arrangedto operate a pilot valve 13, the latter in turn controlling a main valve14 which provides fluid connection from a pump 15 to alternate ends ofthe cylinder in the following manner:-

Referring to Fig. 15, the pilot valve 13 comprises a valve casing 16having a cylindrical bore therein which receives the valve 13. Pressurefluid is admitted to the casing 16 by means of a pair of conduits 17 and18 which are connected to the source of fluid pressure, or pump 15 bythe fluid supply line 20. The Valve casing 16 is provided with outletports 21 and 22 which are connected to opposite ends of the main valve14 by pipes 23 and 24, and an exhaust port 25. The reversing member 12engages the projecting end of valve 13 whereby, in response to movementof said member 12, fluid connection is alternately provided from thepump to opposite ends of the main valve, at the same time connecting theopposite end of the main valve to the exhaust port 25.

The main valve casing 26 which is attached to the front of the machineslidably receives the main valve 14, the latter comprising a hollowcylindrical member, the ends of which are closed by plugs, a divisionalwall 27 being provided between these plugs to divide the interior of thevalve into two chambers. The valve 14, being slidable within the valvecasing, is urged alternately to its end positions in response tomovement of the pilot valve 13 by which movement, fluid under pressureis admitted to opposite ends of said main valve casing. The fluid underpressure, for actuating the carriage 1, is introduced to the main valvefrom the supply line 20 through a pipe connection 28 to a valvemechanism 30 which is arranged to control the speed of the reciprocatorymovement as fully disclosed in Patent No. 1,914,995 above cited. Saidvalve, however, forms no part of this invention, and may be consideredas remaining in the full open position shown during the machineoperation. From this valve 30, the fluid flows through a channel 31 incasing 26 past a manually controlled throttle valve 32 to an inlet port33 adjacent the left hand end of the casing 26 for the valve 14 and asecond inlet port 34 adjacent the right hand end of said casing. Saidcasing also provides outlet ports 33' and 34' connected by pipes 35 and36 to opposite ends of the cylinder 5. With the valve 14 in the positionshown in Fig. 15, it will be apparent that fluid may flow directly fromthe pump 15 through valve 14 to the left hand end of the cylinder 5, thefluid from the right hand end of said cylinder exhausting through thevalve 14 into the exhaust pipe 35 so that the table is moved toward theright, during which movement the dog 7 engages and actuates thereversing member 12, thereby moving the pilot valve to the left andproviding a connection for fluid from the pump to the left hand end ofthe valve 14. This movement of the pilot valve admits fluid to the lefthand end of the casing 26 and thereby actuates the valve 14 to the rightto establish a fluid connection from the pump 15 to the right hand endof the cylinder 5, thereby actuating the table to the left, thealternate movements of the carriage to right and left moving thegrinding wheel over the work surface.

ment of the valve 61 in the following manner:-

The pilot valve having been shifted by the reversing lever 12 during theoutward or right hand movement of the carriage is in a position to causethe carriage to return the grinding wheel to the left into the workpieceupon return of the valve 61 to its original position. It will beremembered that the valve 61 is held in its right hand position by themagnet 53, and in order to release the valve, the magnet is deenergizedduring the outward movement of the carriage" away from the workpiece. Anarm 68, Fig. 14, pivotally mounted on a carrying block on the carriage,and hanging by gravity in the position shown, engages a lug 71 on thepivotally mounted switch 50 during the right hand extended movement ofthe carriage, thereby disengaging the plates 48 and 51 and breaking thecircuit through the electromagnet 53. This movement of the switch 50releases the armature 57, thereby to permit return of the valve 61 toits original position, the return of the valve being effected just afterthe grinding wheel has passed the dressing tool dur-- ing the right handmovement of the carriage.

1A block 72, Fig. 2, which, the same as the carrying blocks 73 and 74for the dogs 7 and 8, is adjustably mounted on the front of saidcarriage, supports a striking dog 75 which is attached to said carryingblock, and a projecting arm 76 of the armature 57 is in the path oftravel of the dog '75. It will be seen that movement to the right of thecarriage will cause engagement of the dog 75 with the arm 76, saidengagement occurring directly after the grinding wheel has passed thedressing tool on the right hand stroke, and will accordingly forciblyreposition the armature and accordingly the depending arm 60, therebymoving the valve member 61 into the original position to establish fluidconnection from the pilot valve 1 13 to the left hand end of the mainvalve 14. As

soon as the valve member 61 is repositioned, the main valve is shiftedby the fluid passing through the pipe line 21 to the left hand end ofsaid valve and the movement of the carriage is reversed,

whereby the grinding wheel is returned to the workpiece for thecompletion of the grinding operation.

During the continued grinding on the workpiece, after the dressingoperation to bring said iworkpiece to finished size, the traversingmovement continues and the workhead is again intermittently movedtransversely of the machine to provide a cross-feed movement, as abovepointed out, so that the grinding operation continues until a rotatinggauge, of the type disclosed in the McDonough Reissue Patent No. 16,141,enters the workpiece to procure cessation of the grinding operation whenthe workpiece reaches the desired finished size. As fully disclosed insaid McDonough patent, a gauge, not shown, is intermittently urgedagainst the end of the workpiece and is arranged to enter within thebore of the workpiece with a longitudinal movement directly as theworkpiece reaches the predetermined finished size, thereby to separatethe wheel and work piece. The longitudinal movement of the gauge intothe bore of the workpiece trips a latch 77, Fig. 14, and allows apivotally mounted arm 78 carrying a gauge contact 88130 swing, therebyto bring said contact into engagement with a stationary contact 81, saidcontacts being normally held in spaced relation by the latch. Engagementof the gauge contacts is arranged to procure an extended movement of thegrinding wheel carriage to the right to separate th grinding wheel fromthe workpiece in the following manner:-

The contact on the arm 78 is grounded at 82 and the contact 81 isconnected by a lead 83 to one terminal of an electromagnet 84, the otherterminal of said magnet being connected by a lead 85 to the lead 54 tothe generator 55. Engagement of the contacts thus completes a circuitthrough magnet 84, thereby energizing the magnet and causing attractionof an armature member 86 pivotally mounted on the same shaft 58 thatforms the pivotal mounting for the armature 57. Attraction of thearmature 86 procures a counterclockwise movement of an upwardlyextending arm 87 and a depending arm 88 both integral with saidarmature. Movement of the upwardly extending arm 87 allows the carriageto move beyond the normal reciprocatory position in an extended movementto the right, and is effected in the following manner:-

The upper end of the arm 87 is normally directly beneath the path oftravel of the left hand table dog 7, Fig. 2, which is pivotally mountedupon the carrying block 7 3 and normally depends by gravity in theposition shown. Raising of the end of the arm 87 engages and lifts thedog 7 so that on the subsequent right hand movement of the carriage 1the dog is lifted entirely clear of the reversing lever 12 and the pilotvalve is, therefore, not shifted to the left whereby the carriagecontinues outwardly to the right carrying the grinding wheel to restposition.

The grinding wheel is brought to rest at the end of its outward movementat the completion of a grinding operation to permit a workloadingoperation to take place. As shown in Fig. 15, a valve 89 which is in thefluid pressure line 36 between the main valve 14 and the right hand endof the cylinder 5 has an upwardly extending stem 90 and is normallyurged into the full open position of Fig. 15 by a spring not shown. Whenthe carriage 1 travels to the right to separate the grinding wheel fromthe workpiece, an abutment, not shown, on the carriage engages a lever,not shown, on the stem 90, thereby rotating the valve 89 and locking thefluid in the right hand end of the cylinder 5, so that the carriage canthereafter move no further to the right. It will be seen, however, thatwhenever the main valve 14 is moved to the right hand position, fluidcan pass to the right hand end of the cylinder 5 by way of thepassage 91which by-passes the valve 89, said by-pass being closed when the valve14 is moved to the left.

Movement of the armature 86 also operates a valve which causes thegrinding wheel to be moved laterally away from the workpiece and therebyto be repositioned for entry, during the grinding of a subsequentworkpiece, into the unfinished bore thereof. depending 88 engages agroove in the valve 92 which moves in a casing 93 provided with an inletport 94 connected to the pressure side of the pump by a pipe 95 and anoutlet port which is connected to a cylinder 96 by a pipe line 97. Saidcylinder has a piston 98 slidable therein which operates to rotate thecross-feed screw shaft 37 counterclockwise by mechanism disclosed in theabove cited Patent No. 1,830,358 and not of itself a part of the presentinvention. Ihis counterclockwise rotation withdraws the cam 40 fromengagement with the adjusting screw 42 into a position for thesubsequent energization of the magnet 53 during the succeeding grindingoperation and places the grinding wheel in the original po- Referring to15, the end of the sition in readiness for another grinding operation.

During the outward movement of the grinding wheel carriage to restposition, rotation of the workhead 3 is stopped in order to permit thereloading of the workholding member. As shown in Fig. 15, a valve casing100 has a pressure port 101 connected by a pipe line 102 to the pressureside of the pump, an outlet port 103 which connects to a cylinder 103and an exhaust port 104. A valve member 105 which normally closes thepressure port is adapted to be rotated during and in response to theoutward movement of the carriage to open the pressure port and to closethe exhaust port, thereby to permit fluid under pressure to flowdirectly to the cylinder 1 03, actuating a piston 106 slidably in thecylinder 103' which operates in any well knownmanner to stop rotation ofthe workholding member. The mechanism for actuating the valve 105 isfully disclosed in the above cited Patent No. 1,914,995.

As movement of the carriage to the right is discontinued by rotation ofthe valve member 89, the right hand end of the piston rod 6, Fig. 1,engages and moves a valve member 107 to the right, thereby to set inoperation the mechanism by which the completed workpiece is removed fromthe workholding member, and an unground workpiece inserted therein.Referring to Fig. 15, the valve member 10'? is slidably mounted in avalve casing 108 which latter has an inlet 110 connected by a pipe line111 to the pipe line 102 which connects to the pressure side of thepump. The casing further has an outlet port 112 connected to the pipeline 113 and an exhaust port 114, the valve 107 being normallymaintained in the position of Fig. 15 by a spring 115 so that the inletport in the casing thereof is normally closed. Movement of the valve tothe right, in response to movement of the carriage, as above pointedout, provides fluid connection between the inlet port 110 and the outletport 112 which sets in operation the workholding instrumentalities. Inorder to more clearly understand the invention, the operating mechanismwill be described before the function of the hydraulic actuatingmechanism therefor.

The workloading mechanism, indicated generally at 116, Fig. 1, ismounted on the right hand end of the workhead directly over theworkholding member or chuck and is supported on the workhead by bolts117 which engage through longitudinal slots 118 in said workloadingmechanism thereby to permit adjustment of the workloading memberrelative to the chuck. The mechanism shown is arranged to be used with adelivery chute of the type shown and described in the above citedHighberg Patent No. 1,846,841, which is not of itself the invention inthe present application, said chute being arranged to be connected tothe upper end of the work-hopper 119 as will hereinafter more clearlyappear. The support for the workloading mechanism comprises a chuckguard 120 having a substantially plane top which provides a widetransverse portion 121 and a portion 122 extending to the lefttherefrom, the latter supporting the actuating mechanism for the loadingmechanism.

The first operation of the \vorkloading mechanism is to remove thecompleted workpiece from the chuck which holds the workpiece in theworkhead 3 by mechanism which is best shown in Fig. '7. A verticalbearing is provided in the forward portion of the chuck guard andsupports a shaft 123 pivotally therein, the lower end of said shaftbeing provided with a work transfer arm 124 fixedly mounted thereon, theouter end of which carries spring members 125 of the type shown in theabove cited Highberg application for engaging within the bore of thecompleted workpiece to support said workpiece. During the grindingoperation, the arm 12 i normally extends forwardly from the shaft 123toward the front of the machine as shown Fig. 1. When the workloadingmechanism is started in operation, the shaft 123 is rotatedsubstantially through a half circle, thereby swinging the am 124 towardthe right and into the chuck so that the spring memb :"s 125 engagewithin the bore of the workpiece and impinge the workpiece thereon; saidarm is then returned substantially to the original position carryingtherewith the completed workpiece, the latter being removed from thespring members during the return movement by mechanism carried on thelower end of the work-hopper 119, Fig. 7, as will hereinafter appear.

Rotation of the shaft 123 is procured in response to rotation of a cam126, Fig. 3, which is operated by iiuid pressure as will be pointed out,movement of said cam being at first counterclockwise throughsubstantially a complete revolution and subsequently clockwise to theoriginal position. A cam groove 12'? having substantially theconfiguration shown in Fig. 5 is engaged by a roller 128, Fig. 4:, onone end of a bell crank lever 130 pivotally mounted on a stud 131 on theportion 121 of the chuck guard, the other end 132 of said bell cranklever being formed as a segmental gear which engages with a pinion 133rigidly mounted on the upper end of the vertical shaft 123. It will thusbe seen that rotation of the cam 126 counterclockwise will swing thework-transfer arm 12% through its entire movement once and subsequentreturn of the cam to its original position will repeat the swingingmovement of the arm 124, the first swinging movement operating to removethe completed workpiece from the chuck, as above set out; the secondswinging movement carrying an unground workpiece into chucking positionand maintaining it until the chuck is actuated to clamp the workpiecesecurely therein. In order to permit the removal of the completedworkpiece, the clamping members of the chuck are released, said releasebeing efiected by the same rotation of the cam that operates thework-transfer arm in the following manner:-

Referring to Figs. 4 and 5, the cam is provided with a cam groove 134which is provided with laterally spaced projections 135 and 136 onopposite sides thereof. A lever 13'? pivotally mounted on a stud 138 onthe portion 121 of the chuck guard carries a roller 139 on one endthereof for engagement in the cam groove 134. The other end of the leveris provided with a handle 1 10 and a roller 1&1 between the pivotalpoint 138 and the handle, the roller 141 engaging a grooved portion in aslidable valve 142, Figs. 4 and 15. During the counterclockwise rotationof the cam, the lever 137, which is normally in the position shown inFig. 1, is engaged by the projection 135 and rocked clockwise as viewedin Fig. l, thereby moving the valve 142 toward the front of the machine.Movement of the valve 142 is arranged to operate the chuck to releasethe clamping members in the following manner:-

Referring to Fig. 15, the valve is shown in the normal position in whichthe chuck is closed, that is, the workpiece is clamped Within the chuck.The casing 143 for the valve 142 is provided with an inlet port 143which is connected to the fluid pressure line by pipes 144, 111 and 102,and is also provided with ports 145 and 146 connected to opposite sidesof a piston, not shown, slidably mounted in a cylinder, also not shown,which operates to open or close the chuck and an exhaust port 147. Withthe valve in the position shown, fluid connection is provided betweenthe inlet port 143 and the port 145 which connects to one end of thecylinder by which the chuck is actuated, thereby maintaining the chuckin closed position, the other end of the cylinder being in fluidconnection with the exhaust port 147 through port 146. Movement of thevalve 142 in response to rotation of the cam establishes fluidconnection between the inlet port 143 and the opposite end of thecylinder through port 146, thereby actuating the draw rod of the chuckto open said chuck and release the workpiece. When the earn 126 isreturned to its original position by clockwise rotation, the projection136 engages the roller 139 on the end of the lever 137 and returns thevalve 142 to its original position at which time the draw rod of thechuck is again actuated, thereby to clamp the unground workpiece whichhas been inserted into the chuck. It will be noted that the cam groove134 is of greater width than the roller received therein, therebypermitting manual operation of the chuck by movement of the handle 140when desired. The piston and cylinder arrangement for actuation of thechuck is well known, and is disclosed in the above cited Highberg PatentNo. 1,840,841.

During the second swinging movement of the workloading arm from theposition shown in Fig. '7, the spring members 125 mounted on the end ofthe arm are adapted to engage unground workpieces and carry them intoclamping position within the chuck. From a consideration of Fig. 7, itwill be seen that the end of the arm 124 carrying the spring members125, passes through the lower end of the hopper 119, the latter beingmore clearly shown in Figs. 10, 11 and 12. The spring members on the endof the arm are adapted to engage workpieces held in the lower end of thehopper and carry them from said hopper, where they are releasablymaintained, into chucking position, the workpieces being supplied to thelower end of the hopper in the following manner:-

The hopper comprises spaced parallel guide members 148 and 149, eachguide member having recesses 159 and 151 therein, Fig. 7, for guidingthe workpieces, the construction shown being arranged to support twoworkpieces in a position for engagement by the workloading arm, bothworkpieces being transferred to the chuck at the same time, and thelatter being adapted to receive both of said workpieces to maintain themsimultaneously in grinding position therein. As will be apparent fromFig. 7, the workpieces are moved downwardly toward the lower end of thehopper by gravity, the column or stack of workpieces being preventedfrom resting on the piece about to be transferred by mechanism actuatedby the loading arm 124 as will hereinafter appear. At the lower end ofthe work hopper, referring to Figs. '7 and 10, separating rails 152 and153 for maintaining the workpieces in spaced relation and end rails 154and 155 are pivotally mounted at 156 and 157, for swinging movement outof engagement with the workpieces, as the work-transfer arm is actuatedthrough the loading movement. Each of these pivotally mounted memberscarries an outwardly projecting arm 158 which is engaged by one end of aspring member 159, the other end of which is attached to a pin 160mounted on the stationary part of the hopper. Adjustable stop members161 and 162 are provided in lugs 163 mounted on the stationf ary part ofthe hopper to maintain the rails in the position shown in Fig. 10. Astop member 164 is carried on the bottom end of each guide rail 146 and149 to prevent the workpieces from pass ing out through the bottom ofthe channels therein. Each of the pivotally mounted rails is bevelled asshown in Fig. 7 at 152, so that as the transfer arm engages theworkpieces, and forces them rearwardly of the hopper, the pivotallymounted rails may swing out of the Way of the workpieces, in response tothe rearward movement thereof, thereby to permit movement or" saidworkpieces from the end of the hopper. It will be apparent that therails are returned to the position of Fig. 10 by the springs 159 as soonas the workpieces carried on the arm have been moved beyond the end ofthe hopper during the loading movement of the transfer arm. Accordingly,the end rails 154 and 155 are in a position during the swinging of thetransfer arm in a subsequent workloading operation to engage with thesides of the completed workpieces carried by the transfer arm during theremoval of said completed workpieces from the chuck, thereby to removesaid completed workpieces from the spring member, the completedworkpieces dropping into a tray or container not shown. It will be notedthat this stripping of the workpieces from the work-transfer arm occursas the arm is swung away from the chuck after having impinged thefinished workpieces on the spring members, as above pointed out.

Since the removal of the completed workpieces from the chuck occursduring a workloading operation prior to the insertion of ungroundworkpieces, the hopper is arranged to maintain the unground workpiecesaway from the lower end of the hopper during the first swinging movementof the transfer arm in order to permit said arm to swing freely, therebyto carry the spring members on said arm into engagement with thecompleted workpieces. The unground workpieces to be loaded in the chuckare arranged to fall by gravity into the lower end of the hopper at theend of the first swinging movement of the transfer arm and to accomplishthis, mechanism is provided which controls the position of the ungroundworkpieces and which is actuated by movement of the transfer arm in thefollowing manner:-

Referring to Figs. 7 and 13', spaced lugs 165 and 166 are adapted to beinserted in slots 167 168 formed in the guide member 148 and are adaptedto be moved alternately into and out of workpiece engaging position inorder to permit two workpieces to drop into position for engagement bythe work-transfer arm and to maintain the remaining workpieces out ofengagement with said first workpieces, thereby preventing the entirecolumn of workpieces from resting on the pieces to be transferred to thechuck. The vertical spacing of the lugs 165 and 166 is such that whenthe stack of workpieces is resting on the lower lug 166, the upper lugmay move between the workpieces resting on the lower lug and the nextsucceeding workpieces thereabove, whereby the upper lug 165 will supportthe stack of workpie es when the lower lug 166 is withdrawn, permittingonly the lowermost workpieces in the stack to drop into workloadingposition. Similarly, when the lower lug is in a position to prevent theworkpieces from moving into the bottom of the hopper, the upper lug maybe removed, thereby to permit the column of workpieces to move down bygravity to rest on the lower lug 165; said upper lug may thereafter bereturned for engagem nt between the lowermost work pieces resting on thelow-er log and the next succeeding workpieces above. It will be notedthat there are two columns of workpieces in parallel relation in thehopper, so that the lowermost workpieces in the two columns are loadedand controlled as a unit.

lhe lugs 185 and 166 are t ithdrawn and returned to work-engagingposition in response to movement of the work-transfer arm, the upper andlower lugs 165 and 166 being provided respcctively with circular rods1'13 and 174 extending therefrom. A bracket 175 which is mounted uponthe front or" the chuck guard by bolts 176 and 1'77 provides bearings178 and 179 for said rods in an arm 189 integral with said bracket.Movement of the rod 173 in its bearing 178 is limited by a collar 181locked in position on said rod by a set screw 182 on one side of saidbearing and a similar collar 183 on the opposite side of said bearinglocked on said rod by a set screw 184, said latter collar providing astud forming pivotal support for an arm 186 by which said rod isactuated. A stud bolt 18'! mounted in a hub 188 formed on the bracket175 provides a bearing surface on which a member 190 is slidablymounted, said member having an arm 191 similar to the arm 180, said arm191 providing bearings for the rods 173 and 174, the latter rod 174being held against sliding movement in said arm by a set screw 192. Themember 190 has a stud 193 thereon which engages an elongated slot 194 inthe arm 186, providing a pivotal support for said arm. The arm 186depends below the elongated slot 194 and is provided with a boss 195which receives a screw threaded mem=- her 196 adjustably held therein byadjusting nuts 19'? and 198. Th end of the screw threaded member 196carries a rigidly mounted depending arm 200 thereon, the lower end ofsaid arm carrying an adjustable stud 201 held in adjusted position byadjusting nuts 202 and 203. A pin 204 formed on said boss 195 is engagedby one end of a spring 295, the other end of which is carried by a pin206, Fi 7, mounted on the hopper, the spring tending to urge the lowerend of said arm 188 toward the right, thereby to urge said me i:

her 190 into engagement with the hub 188.

In the normal position of the arm 186 in which the arm 124 is rotatedcounterclockwise from the position shown in Figs. '7 and 13, and out ofengagement with stud 201, the lower lug 166 is in position to preventworkpieces from passing down through the hopper, and the upper lug 165is withdrawn from work-engaging position. It will be apparent that asthe stud 201 is engaged by the work-transfer arm, Fig. 7, the arm 186 isrocked clockwise from normal position against the action of the spring265 into the position shown in Figs. 7 and 13.

From a consideration of Fig. 5, it will be ap-- parent that thework-transfer arm, whi h is actuated by movement of the cam 126, isrotated beyond the normal position of said arm at the end of the firstswinging movement, that is, at the end of the movement for removing thecompleted workpiece, whereby said arm engages the stud 201 and actuatesthe work-feeding mechanism to allow an unground workpiece to drop intoposition in the lower end of the hopper between the unloading movementand the loading movement of the arm 124.

In order to understand the operation of the lugs 165 and 166, the worktransfer arm operates briefly as follows:'1he work-transfer arm startsfrom normal or rest position, that is, a position somewhat beyond theposition shown in Fig. 7, such that the arm is out of engagement withthe stud 201 when said stud is in the normal position. The work-transferarm 124 is first rotated countel-clockwise in response to rotation ofcam 126 carrying the spring members on the end thereof through the lowerend of the hopper, the latter having no workpieces in the lower endthereof during this movement, said spring members being ultimatelybrought into engagement with the bore of the completed workpieces in thechuck. The jaw members of the chuck having been pr viously released, thework-transfer arm carrying the workpieces thereon, is then swungclockwise to swing the outer end thereof back between the lower ends ofthe guide members 148 and 149, the completed workpieces being withdrawnfrom the spring members, by engagement of the plates 154 and with theworkpieces. During this clockwise rotation of the work-transfer arm, byreason of the shape of the actuating cam 126, the arm 124 is carriedbeyond the normal position of rest into the position shown in Fig. 7, inorder to engage the adjusting stud 201, thereby rocking the arm 186clockwise to allow unground workpieces to drop into the lower end of thehopper for engagement with the spring members 125 during the subsequentcounterclockwise rota tion of the work-transfer arm during the loadingmovement. Said arm 124, during its second counterclockwise rotation,engages said workpieces and carries them out of the hopper against theholding action of the rails 152, 153, 154 and 155 into chucking positionwithin the workholder, after which the arm rotates clockwise to withdrawsaid spring members from the workpieces, said arm returning to itsoriginal position of rest, out of engagement with stud 2G1.

The operation of lugs and 166 in response to engagement of the stud 261by the work-transfer arm is as follows:-A.s above pointed out, the arm186 is normally urged counterclockwise by the action of the spring 20F-to bring the collar 181 into engagement with the arm 1811, therebywithdrawing the lug 155 from work-engaging position and urging the lug166 into work-engaging position in response to sliding movement oi theright. It will thus be seen that the normal position of the arm is suchthat the lower lug 1.86 is in work-engaging position, the member restingagainst the hub and the upper lug 165 is withdrawn from work-engagingposition. j' i From this normal position,

the lugs are actuated by engagement of the work-transfer arm with thestud 201 at the end of the first swinging movement of said arm.Referring especially to Fig. 13, the counterclockwise movement ofwork-transfer arm moves th stud 201 to the left, thereby urging the arm185 clockwise. The position of the spring 205 tends to hold the slidablemember 190 toward the right so that the lug 165 is actuated to the rightand into work engaging position before the slidable member 190 isactuated to the left, the stud 193 on the slidable member acting as apivot for the arm 186. When the lug 165 is in work-engaging position,the

collar 183 engages the arm 1811 so that continued mar-her 190 toward themovement of the stud 201 to the left carries the slidable member 190toward the left, thereby withdrawing the lower lug 166 to the left outof work-engaging position so that the lowermost workpieces drop into thebottom of the hopper, the remainder of the stack being supported by lug165. The subsequent swinging movement of the work=transfer armcounterclockwise, as above pointed out, permits the stud 201 to returnto its normal position, whereby the member 190 is urged to the right tomove the lug 166 again into work-engaging position and, when the bearingmember 190 comes in contact with the hub 188, continued rocking of thearm 186 by said spring 205 withdraws the lug 165 from work-engagingposition, thereby returning the parts to the original position.

Movement of the lugs 165 and 166 accordingly occiu's in the followingorder beginning from the normal position in which the lower lug 166 isin work-engaging position and the upper lug is withdrawn therefrom.Considering the Workpieces in one of the columns, in response tomovement of the work-transfer arm, the upper lug is urged intowork-engaging position to support all the workpieces except thelowermost one which is between lugs 165 and 166, after which the lowerlug is withdrawn, thereby allowing said lowermost workpiece to drop intothe lower end of the hopper for engagement by the spring men bers on theend of the work-transfer arm. Subsequently the lower lug is returned toworkengaging position to prevent movement of the stack into the bottomof the hopper after which the upper lug is withdrawn therefrom inresponse to the return movement of the arm 186 to normal position toallow the stack of workpieces to drop from the position above the upperlug into position against the lower lug where they are supported inreadiness for the delivery of the lowermost workpiece to the lower endof the hopper during the succeeding workpiece loading operation.

As above pointed out, movements of the workloading mechanism occur atthe end of a grinding operation and are initiated by engagement of thevalve 107 with the end of the piston rod 6 during the runout of themachine to rest position. Referring to Fig. 15, the outlet port 112 ofthe valve 107 is connected by the pipe 113 to spaced inlet ports 208 and210 in a casing 211 for a valve 212, said casing being provided withspaced outlet ports 213 and 214 which are connected to inlet ports 215and 216 at opposite ends of a valve casing 217 by pipes 218 and 220respectively. The casing 211 is provided with an enlarged bore 221, Fig.9, at one end thereof to receive the enlarged end 222 of the valve 212,arranged in such a manner that iiuid under pressure entering the port208 will urge the valve 212 toward the left. In the normal position ofthe valve, as shown in Figs. 9 and 15, fluid connection is providedbetween the inlet port 210 and the outlet port 213 so that when fluidunder pressure passes through the pipe 113, it is carried directlythrough the casing 211 into the left hand end of the casing 217, theright hand end of the casing being connected to an exhaust outlet 223through the pipe 220. In this position of the valve 212, the fluid underpressure passing through casing 211, actuates a piston 224 slidable inthe casing 217 toward the right, and procures rotation of the cam member126 in the following manner- Referring to Figs. 3 and 8, it will be seenthat the piston 224 is provided with a piston rod 225,

the projecting end of which is enlarged and formed to provide a rackmember 226. As shown in Fig. 3, the casing 217 is mounted on theextending portion 122 of the chuck guard 120 with the piston rodextending toward the right, as seen from the. front of the machine, theouter end of said piston rod 225 being supported in a bearing 227mounted on the portion 121 of the chuck guard. Said bearing provides aset screw 228 engaging a groove 229 in the piston rod, therebysupporting the rack 226 against rotation. The cam 126 is supported atopposite ends in bearings 230, formed on the chuck guard 120, and isprovided with a pinion 231 for engagement with the rack 226. Movement ofthe piston toward the right, in response to movement of valve 107,procures rotation of the cam counterclockwise, thereby procuring thefirst swinging movement of the workloading arm through swinging movementof the gear segment 132 to procure the unloading of the completedworkpiece from the workholding member.

As the piston 224 reaches the right hand end of its stroke, the flow offluid under pressure to the casing 217 carrying said piston is directedto the right hand end thereof (Fig. 15) to return said piston to theleft hand end of the cylinder, thereby rotating the cam 126 clockwise tocomplete the operation of the workloading mechanism, that is, totransport an unground workpiece from the lower end of the hopper intoworkclamping position within the chuck. From a consideration of Fig. 15,it will be apparent that fluid entering the port 208 tends to urge thevalve member 212 to the right in which position pressure fluid from thepump will be admitted to the right hand end of the casing 217. Movementof the valve 212 does not occur, however, until the piston 224 hasreached the right hand end of travel, the valve 212 being held againstmovement to the right in the following manner:

Referring particularly to Figs. 4, 5 and 9, the valve 212 has anextension thereof, provided with a groove 232 which receives one end ofa bell crank lever 233, the latter being pivotally mount ed on a stud234 on the extending portion 122 of the chuck guard, the other end ofsaid lever having a roller 235 thereon which engages in a cam groove 236in said cam. The cam groove comprises two parallel circular grooves 237and 238 interconnected at opposite ends. During the initial movement ofthe cam, the roller 235 is in the circular groove 237, therebypreventing rocking of the bell crank lever 233 and maintaining the valve212 in its extreme right hand position. At the end of the counterclockwise rotation of the cam, when the piston 224 is in the extremeright hand position, the roller 235 is allowed to move from groove 237to groove 238 at the point where said grooves are interconnected,thereby permitting the valve 212 to move to the left in response to thefluid under pressure passing into port 208. Movement of the valve 212provides fluid connection from the pump to the right hand end of thecasing 217 and connects the left hand end of said casing to the exhaustport 223, whereby the piston 224 is urged to the left rotating the camclockwise to return said cam to its original position. During the latterclockwise rotation of the cam, the work-transfer arm is swung throughits loading movement, thereby carrying the unground workpiece intowork-chucking position.

As the cam 126 is returned to its original position, the ungroundworkpiece now having been placed in the workholding member, theworkloading operation being thus completed, the carriage 1 is startedfrom rest position, carrying the grinding wheel to the left and intooperative relation with the unground workpiece, in the followingmanner:-

Referring to Figs. 8 and 15, the casing 217 for the piston 224 isprovided with a channel 240 from the bore for said piston to acylindrical bore 241 in the casing 217; said bore 241 receives aslidable valve member 242, the latter being normally urged into extremeright hand position by a spring member 243 which engages at one end withthe cylinder head 244 provided for said casing and at the other end withan enlarged flange 245 on the end of said valve. The cylindrical bore241 has an outlet port 246 connected by a pipe 247 to the right hand endof the casing for the pilot valve 13 and an exhaust port 248, fluidconnection being provided between said outlet port 246 and the exhaustport 248 in the normal position of the valve as shown in Fig. 15,thereby normally having no effect on the movement of the pilot valve 13.The valve 242 is urged to the left at the completion of the workloadingoperation to establish fluid connection from the channel 240 to theoutlet opening, thereby admitting fluid under pressure to the right handend of the pilot valve 13, this movement occurring just before thepiston 224 reaches normal position on the return stroke. As shown inFigs. 4 and 8, a link 250 is comiected to the bell crank lever 233 atone end and is provided on the opposite end with a roller 251 whichengages in a groove 252 provided by the flange 245 on the end of thevalve 242. The latter end of the link also carries an upstanding stud253 which engages with a stop member 254 mounted on the extension of thepiston rod 225 for the piston 224. Swinging movement of the bell cranklever 233, during the operation of the workloading mechanism as abovepointed out, actuates the link to place the stud 253 in a position forengagement with the stop member 254 during the left hand movement of thepiston 224 to its original position (said movement being to the right inFig. 8), thereby moving the valve 242 to the left, Fig. 15, andproviding fluid connection through the channel 240 to the outlet port246 and closing the exhaust port 248, whereby fluid under pressure isadmitted to the right hand end of the pilot valve, thereby to actuatesaid valve and initiate the return movement of the grinding wheelcarriage into operative position.

.As movement of the table or carriage to the left is begun, the end ofthe piston rod 6 is withdrawn from contact with the valve 107, therebypermitting said valve to be urged to the left in response to the spring115 so that the inlet port in the casing 108 is closed, the exhaust portbeing at that time opened to relieve the fluid pressure in the pipe line113. This relieves the pressure in the bore 221 of the casing 211,thereby permitting the valve 212 therein to return to the right into itsoriginal position under the influence of a spring 255, Fig. 9, whichengages between the end of said casing and a flange 255 on said valve.This movement places the valve in a position to permit a subsequentworkloading operation to take place at the completion of a subsequentgrinding operation.

During the movement of the valve 212 to the right at the end of theloading operation, the bell crank lever 233 is rocked, thereby placingthe roller in the end of the circular groove 237 to permit said bellcrank lever to function during the succeeding workloading operation inholding the valve in desired position. In order to prevent the valve 212from sliding to the left, Fig. 15, immediately as fluid under pressureis allowed to enter the enlarged bore 221 at the beginning of aworkloading operation, a latch member is provided to hold th roller onthe end of the bell crank lever 233 in the end of groove 237, therebypreventing swinging movement of the lever and accordingly holding thevalve 212 in right hand position. Referring to Fig. 6, a latch member257 is received within a recess 258 formed in the earn 126, said latchbeing pivotally mounted on a pin 260. The projecting end 261 of thelatch extends into the groove connecting the grooves 237 and 238 at oneend thereof and is normally held outward in roller engaging position bya spring 262 within the recess, outward movement of the latch 25"! inresponse to said spring being limited by a projecting portion 263 ofsaid lever which engages a portion of the cam. It will be seen that, asthe bell crank lever swings, thereby to move the roller from the groove238 into the groove 237 at the completion of a workloading operation,the latch is depressed to permit this swinging movement and is thenurged outwardly to prevent rocking movement of the bell crank leverwhich would move the roller back into the groove 238, thereby holdingthe valve 212 to the right until the cam 126 has been rotatedcounterclockwise during the workloading operation, as above pointed out.

Swinging movement of the bell crank lever 233, at the end of theworkloading operation, withdraws the stud 253 from engagement with thestop member 254, thereby permitting the valve 242 to return to originalposition in readiness to perform its function during the succeedingloading operation. Return of valve 242 to original position connects theright hand end of the pilot valve 13 to the exhaust, so that the pilotvalve may be actuated during the succeeding grinding operation.

As the pilot valve 13 is urged to the left, in response to movement ofthe valve 242 as above pointed out, the main valve 14 is actuated to theright, thereby opening the passage 91 Which bypasses the valve 89,whereby fluid may flow from the pump to the right hand end of thecylinder 5, thereby urging the carriage to the left carrying thegrinding wheel into operative relation with the workpiece to procure agrinding operation. As the carriage is moved, the abutment which engagesthe upwardly extending lever on the stem 90 is withdrawn from engagementtherewith, thereby allowing the valve 89 to return to original openposition, and during the same movement of the table or carriage intooperative position, an arm 264 pivotally mounted on the carrying block70 on the front of the carriage engages a ing 265 on the pivotallymounted switch 50, thereby returning said switch to its originalposition for subsequent functioning during a succeeding grindingoperation.

To summarize briefly the operation of the ma- I ing is continued withthe grinding wheel in operative relation to the workpiece until theworkpiece is ground nearly to a finished size when a dressing operationis performed on the wheel after which grinding is again resumed until agauge enters the bore 01 the workpiece just as the workpiece reaches thepredetermined size, thereby procuring separation of the grinding wheelcarriage from the workholding member to permit the workloading mechanismto operate. During the separation of the grinding wheel and workloadingmember, cross-feed movement of the workholding member relative to thegrinding wheel is retracted in order to place the members in theoriginal position in readiness for a subsequent grinding operation. Thegrinding wheel carriage is carried away from the workpiece and isbrought to rest by the rotation of valve 89, thus locking fluid in theright hand end of the cylinder 5 and preventing movement or" thecarriage to the right, the valve 13 being in the right hand position inwhich the normal movement of the carriage is toward the right. Just asthe carriage is brought to rest, the right hand end of the piston rod 6engages a valve 10? thereby admitting fluid under pressure through thevalve 212 and into the left hand end of casing 217, thereby actuatingthe piston 224 to the right, rotating the cam 126 counterclockwise toswing the workloading arm 12% from the normal position around throughthe lower end of the hopper (there being no workpieces therein at thistime) and into the bore of the completed workpiece. The samecounterclockwise movement of the cam 126 moves the valve 142 through thelever 137 thereby releasing the clamping members within the workholdingmember. The workpiece now being impaled on the spring members 1 25,rotation of the arm clockwise withdraws the workpiece from theworkholding member and as the arm passes through the lower end of thehopper during this return movement, the workpiece is stripped from saidspring members. The above swinging movement of the workloading armoccurs in response to and during the right hand movement of the piston224, and as the piston reaches its right hand end of stroke, the valve212 is actuated in response to fluid under pressure to admit fluid tothe right hand end of the cylinder 217, thereby to actuate the piston224 to the left. Fnis return movement of the piston actuated theworkloading arm through its loading operation carrying a workpiece fromthe lower end of the hopper into the workholding member. The workholdingmember is then closed in response to movement of valve 142 while theworkpiece is supported within the workholding member by the workloadingarm and subsequent return movement of the workloading arm withdraws thespring members 125 from the bore of the workpiece. The ungroundworkpieces are supplied to the lower end of the hopper before theworkloading arm is swung through the loading movement, said arm beingswung at the end of the unloading operation into engagement with a stud201, thereby withdrawing the lug 166 from the recesses 150 and 151 toallow a workpiece to drop into the bottom of the hopper.

Just before the piston 224 reaches its original position in the lefthand end of the casing 217, a stop carried by the piston rod 225 forsaid piston actuates the valve 242 to the left, thereby permitting fluidunder pressure to pass through said valve 242 into the right hand end ofthe casing 16, thereby actuating the pilot valve 13 to the left to startthe grinding wheel carriage in toward the left to carry the grindingwheel into operative relation with the unground workpiece which has now'been substituted for the completed workpiece.

tion and brought to rest at which time the Workloading instrumentalitiesare set in operation in response to the movement of the carriage. Theworkloading instrumentalities having been set in operation, thecontinued operation thereof is independent of the remainder of themachine, the entire operation of removing the completed workpiece andinserting the new workpiece occurring in response to fluid underpressure. After the workloading is completed, the grinding wheel isreturned to operative relation with the unground workpiece in responseto mechanism controlled by the workloading instrumentalities.

I claim,

1. In a grinding machine, a grinding wheel and a workholder in operativerelation thereto, means to procure separation of said wheel from saidmember at the completion of a grinding operation, workloading means,means responsive to said separation to initiate the operation of saidworkloading means, and means actuated by said workloading means toreturn the wheel to operative position relative to the workholder.

2. In a grinding machine, a grinding member and a workholding member inoperative relation thereto, means to procure separation of said membersat the completion of a grinding operay tion, workloading means for theremoval of a completed workpiece from the workholding member and theinsertion of an unground workpiece therein, means to'initiate theoperation of said workloading means in response to the separation ofsaid members, and means set in operation after the unground workpiecehas been inserted in the workholding member to return said members tooperative position.

3. The combination with a workholder having clamping means adapted toclamp a workpiece, of a workloading mechanism comprising means to openand close said clamping means, and means to remove a finished workpiecefrom said workholder and to insert another workpiece therein while saidclamping means are open, said workloading mechanism being actuated byfluid under pressure.

4. The combination with a workholder having clamping members adapted toclamp a work" piece, of a workloading mechanism comprising means to openand close said clamping members, a wcrk carrier, and means to actuatesaid work carrier to remove a completed workpiece from said workholderand to insert another workpiece while said clamping means are open, saidlast means also actuating the means for opening and closing the clampingmembers.

5. The combination with a workholder having clamping members adapted toclamp a workpiece, of a workloading mechanism comprising means to openand close said clamping members, work carrying means to remove aworkpiece from said workholder and to insert another workpiece therein,means actuated by said work carrying Leo rho

Lido

means to place workpieces successively in a position for engagement bysaid carrying means for insertion in the workholder, and fluid pressuremeans to actuate said workloading mechanism,

6. The combination with a workholder having clamping members adapted toclamp a workpiece, of a workloading mechanism comprising means to openand close said clamping members, work carrying means to remove aworkpiece from said workholder and to insert another workpiece therein,means actuated by said work carrying means to place successiveworkpieces in position for engagement by said carrying means forinsertion in the workholder, and means to actuate said workloadingmechanism.

7. In a machine of the class described, a workholding member adapted toclamp a workpiece therein, and a workloading mechanism comprising meansto release a workpiece from said workholding member, means to remove aworkpiece from said member and to insert another workpiece therein, andmeans thereafter to clamp the latter workpiece in said workholdingmeans, means to set said workloading mechanism in operation, saidworkloading mechanism being automatically carried through an entireworkloading operation after having been set in operation.

8. In a grinding machine adapted for the reduction of successiveworkpieces to a predetermined size, a grinding member, a workholdingmember having a workpiece secured therein, means to procure axialseparation of said members when the work piece has been ground to apredetermined size, workloading mechanism for the removal of thecompleted workpiece from the workholding member and the insertion of anunground workpiece therein, said mechanism being set in operation inresponse to the separation of said members, and means to return saidmembers into operative relation after the unground workpiece has beeninserted in the workholding memher.

tion when the workpiece being ground has reached the predetermined size,means responsive to said separation to procure retraction of thecross-feed movement, workloading mechanism, means responsive to theseparation of said members to initiate the operation of said workloadingmechanism, and means to return said members into operative relation atthe end of the workloading operation.

10. A workloading mechanism for the automatic insertion of workpieces ina workholder, the latter comprising chucking means to release and toclamp a workpiece in the holder, said mechanism comprising a workcarrier arranged to remove said workpiece from the holder and to insertanother workpiece therein, means to remove a workpiece from the carrierand to maintain another workpiece in position for engagement with saidcarrier, and means for automatically actuating said chuck operatingmeans and work carrier through an entire workloading operation.

11. A workloading mechanism for the automatic insertion of workpieces ina workholder, the latter comprising chucking means to release and toclamp a workpiece held in the holder,

said mechanism comprising a work carrier arranged to remove saidworkpiece from the holder and to insert another workpiece therein, meansto remove said workpiece from the carrier and to support the otherworkpiece in position for engagement with said carrier, and means tooperate said chucking means, said workloading mechanism being actuatedby fluid under pressure through an entire loading operation.

12. In a grinding machine, a grinding member, a workholding member inoperative relation thereto, means to procure separation of said membersat the completion of a grinding operation, workloading means for theremoval of a completed workpiece from the workholding member and theinsertion of an unground workpiece therein, means to initiate theoperation of said workloading means in response to the separation ofsaid members, and means responsive to said workloading means, andactuated after the unground workpiece has been secured in theworkholding member to return said members to operative position.

13. In a machine of the class described, a wor holding member adapted toclamp a workpiece therein, a workloading mechanism comprising means torelease a workpiece from said workholding member, a work carrier for theremoval of a workpiece from said member and the insertion of anotherworkpiece therein, and means to clamp the latter workpiece in saidworkholding means, said workloading mechanism being automaticallycarried through an entire workloading operation.'

14. In a machine of the class described, a workholding member adapted toclamp a workpiece therein, a workloading mechanism comprising means torelease a workpiece from said workholding member, a work carrier for theremoval of a workpiece from said member and the insertion of anotherworkpiece therein, means to clamp the latter workpiece in saidworkholding means, means actuated by said work carrier for positioningof the latter workpiece for engagement with the work carrier, and meansto actuate the workloading mechanism whereby said mechanism isautomatically actuated through an entire loading operation.

15. In a grinding machine adapted for the reduction of successiveworkpieces to a predetermined size, a grinding member, a workholdingmember having a workpiece secured therein, means to procure a cross-feedmovement between said members, means to procure axial separation whenthe workpiece being ground has reached the predetermined size, meansresponsive to said separation to procure retraction of the cross-feedmovement, workloading mechanism comprising means to release and clampworkpieces in the workholding member, means to remove a workpiece fromsaid member and insert another workpiece therein, means responsive tothe separation of said members to set said workloading mechanism inoperation, and means to return said members into operative relation atthe end of the workloading operation.

16. In a grinding machine adapted for the reduction of successiveworkpieces to a predetermined size, a grinding member, a workholdingmember having a workpiece secured therein, means to procure a cross-feedmovement between said members, means to procure axial separation whenthe workpiece being ground has reached the predetermined size, meansresponsive to said separation to procure retraction of the cross-feedmovement, workloading mechanism comprising;

LAO

tion of said members to said workloading mechanism in operation, andmeans to actuate said workloading mechanism through an entireworkloading operation after having been set in operation, said lastmeans procuring the return or said members into operative relation atthe close or" the loading operation.

17. A workloading mechanism for the automatic insertion of workpieces ina workholder having chucking means to release or clamp a workpiece insaid holder, said mechanism com' prising a work carrier for the removalof a workpiece from and the insertion of a workpiece into said holder,means to remove a workpiece from said carrier and to place anotherworkpiece thereon, means to operate said chucking means, and actuatingmeans for the operation of the work carrier and said chuck operatingmeans, said actuating means being adapted to operate the mechanismthrough an entire workloading operation, and to bring the mechanism to astop at the end or" said operation.

13. The combination with a workholder having clamping means adapted tosupport a workpiece removably therein, of a workloading mechanismcomprising means to remove a finished workpiece from said workholder andto insert another workpiece therein, said worklcading mechanism beingactuated directly by fluid under pressure.

19. The combination with a workholdcr having clamping members adapted toclamp a workpiece rernovably therein, of a workloading mechanismcomprising work carrying means to remove a workpiece from saidworkholder and to insert another workpiece therein, means actuated bysaid work carrying means to place workpieces successively in a positionfor engagement by said carrying means for insertion in the workholder,and fluid pressure means to actuate said workloading mechanism.

20.111 a machine of the class described, a work holding member, aworkloading mechanism comprising means to remove a workpiece from saidmember to insert another workpiece therein, and means to set saidworkloading mechanism in operation, said workloading mechanism beingautomatically carried through an entire workioading operation afterhaving been set in operation.

21. In a machine of the class described, a

, workholding member a workloading mechanism com rising means to removea workpiece from said member and to insert another workpiece therein,means to set said workloading mechanism in operation, and fluid pressuremeans for automatically actuating said workloading mechanism through anentire workloading operation after said mechanism has been set inoperation.

22. In a grinding machine adapted for the reduction of successiveworkpieces to a predetermined size, a grinding member, a workholdingmember having a workpiece secured therein, means to procure axialseparation of said members when the workpiece has been ground to apredetermined size, workloading mechanism for the removal of thecompleted workpiece from the workholding member and the insertion of anunground workpiece therein, said mechanism being set in operation inresponse to the separation of said members, and means responsive to theoperation of the workloading mechanism to return said members intooperative relation after the unground workpiece has been inserted in thewcrkholding member.

23. In a grinding machine adapted for the reduction of successiveworkpieces to a predetermined size, a grinding member, a workholdingmember having a workpiece secured therein, means to procure a cross-feedmovement between said members, means to procure axial separation whenthe workpiece being ground has reached the predetermined sire, meansresponsive to said separation to procure retraction of the cross-feedmovement, workloading mechanism, means responsive to the separation ofsaid members to initiate the operation of said workloading mechanism,and means actuated by said workloading mechanism to procure return ofsaid members into operative relation at the end of the workloadi-ngoperation.

2 In a grinding machine adapted for the reduction of successiveworkpieces to a predetermined size, a grinding member, a workholdingmember having a workpiece secured therein, means to procure axialseparation of said members when the workpiece has been ground to apredetermined size, workloading mechanism for the removal of thecompleted workpiece from the workhoiding member and the insertion of anunground workpiece therein, means responsive to the separation of saidmembers to set said workholding mechanism in operation, fluid pressuremeans to actuate said workloading mechanism through a workloadingoperation, and means actuated by said workioading mechanism to returnsaid members into operative relation at the completion of theworkloading operation.

25. In a grinding machine adapted for the reduction of successiveworkpieces to a predetermined size, a grinding member, a workholdingmember having a workpiece secured therein, means to procure a cross-feedmovement between said members, means to procure axial separation of saidmembers when the workpiece being ground has reached a predeterminedsize, means responsive to said separation to procure retraction ofcross-feed movement, workloading m chanism, means responsive to theseparation of said members to initiate the operation of said workloadingmechanism, fluid pressure means to actuate said workloading mechanism,and means actuated by said workloading mechanism to procure return or"said members into operative relation at the end of the workloadingoperation.

26. In a grinding machine, the combination with a grinding member, aworkholding member in operative relation thereto, and means to procureseparation of said members at the completion of a grinding operation, ofworkloading means for the removal of a completed workpiece from theworkholding member and the insertion of an unground workpiece therein,means to initiate the operation of said \vorkloading means in responseto the separation of said members, fluid pressure means to actuate saidworkloading means through a workloading operation, and means responsiveto the movement of said workloading means and actuated after theunground workpiece has been secured in the workholding member to returnsaid members to operative position.

2'7. In a machine of the class described, a workholding member adaptedto clamp a workpiece therein, a workloading mechanism comprising meansto release a workpiece from said workholding member, a work carrier forthe removal of a workpiece from said member and the insertion of anotherworkpiece therein, and means to clamp the latter workpiece in saidworkholding means, and fluid pressure means for automatically actuatingsaid. workloading mechanism through an entire workloading operation.

28. In a machine of the class described, a workholding member, aworkloading mechanism comprising a work carrier for the removal of aworkpiece from said member and the insertion of another workpiecetherein, means actuated by said work carrier for positioning of thelatter workpiece for engagement by said work carrier, and fluid pressuremeans to actuate the workloading mechanism through an entire workloadingoperation.

29. In a grinding machine adapted for the reduction of successiveworkpieces to a predetermined size, the combination with a grindingmember, a workholding member having a workpiece secured therein, meansto procure a cross-feed movement between said members, means to procureaxial separation of said members when the workpiece reaches apredetermined size, and means responsive to said separation to procureretraction of the cross-feed movement, of a workloading mechanismcomprising means to remove a workpiece from said member and insertanother workpiece therein, means responsive to the separation of saidmembers to set said workloading mechanism in operation, fluid pressuremeans to actuate said workloading mechanism through an entireworkloading operation, and means actuated by said workloading mechanismto procure return of said members into operative relation at the end ofthe workloading operation.

30. In a grinding machine adapted for the reduction of successiveworkpieces to a predetermined size, the combination with a grinding member, a workholding member having a workpiece secured therein, means toprocure a cross-feed movement between said members, means to procureaxial separation of said members when the workpiece reaches apredetermined size, and means responsive to said separation to procureretraction of the cross-feed movement, of a workloading mechanismcomprising means to remove a workpiece from said member and insertanother workpiece therein, means responsive to the separation of saidmembers to set said workloading mechanism in operation, fluid pressuremeans to actuate said workloading mechanism through an entire loadingoperation and to bring said mechanism to a stop at the end of saidoperation, and means actuated by said workloading mechanism to returnsaid members into operative relation at the end of the workloadingoperation.

31. A workloading mechanism for the automatic insertion of workpieces ina workhclder, the latter comprising chucking means to release and toclamp a workpiece in the workhclder, said mechanism comprising a workcarrier arranged to remove a completed workpiece from the holder and toinsert another workpiece therein, means to remove said finishedworkpiece from the carrier and to maintain the other workpiece inposition for engagement with said carrier, and fluid pressure means foractuating said workloading mechanism through an entire workloadingoperation and for bringing said mechanism to rest at the end of saidoperation.

32. In a grinding machine, a grinding member and a work-supportingmember, means to procure a relative separation of said grinding memberfrom a workpiece in said work-supporting member at the completion of agrinding operation, workloading means for procuring removal of acompleted workpiece from the work-supporting member and the positioningof an unground workpiece therein, means to initiate the operation ofsaid workloading means in response to the separation of said members,and means actuated by said work loading means to return the grindingmember into operative relation to the workpiece in the work-supportingmember.

33. In a grinding machine, a grinding member and a work-supportingmember, means to procure a relative separation of said grinding memberfrom a workpiece in said work-supporting member at the completion of agrinding operation,

workloading means for procuring removal of a completed workpiece fromthe work-supporting member and the positioning of an unground workpiecetherein, means to initiate the operation of said workloading means inresponse to the separation of said'members, fluid pressure means forautomatically actuating said workloading means through an entireoperation, and means set in operation after the unground workpiece hasbeen positioned in the work-supporting member for returning saidgrinding member to operative position relative to the workpiece in theworksupporting member.

WALDO J. GUILD.

